永磁球形电机的少保守性滑模控制
Less conservative sliding mode control of permanent magnet spherical motor

永磁球形电机轨迹跟踪控制方法常常利用高增益的控制输出来保证系统的鲁棒性及跟踪控制的快速性. 但这种保守控制会带来较大的控制作用, 甚至导致执行器饱和. 为了减少控制的保守性, 本文设计了一种带有非线 性干扰观测器的模糊滑模控制器来解决球形电机的轨迹跟踪问题. 利用干扰观测器对不确定性、摩擦、外界干扰、 负载扰动等进行估计, 并在控制输入端进行补偿实现对干扰的抑制. 并利用滑模控制器抵消干扰观测器的干扰观测 误差及不可观测部分的干扰, 为了减少滑模的抖振, 本文利用模糊逻辑对该部分进行逼近, 并利用模糊的输出增益 代替滑模的切换增益. 此外通过Lyapunov方程证明了本文控制器的稳定性. 仿真结果表明在存在模型不确定性及 各种干扰的情况下, 本文的轨迹跟踪控制具有良好的动静态性能和少保守性.
The high gains output is often adopted in the existing permanent magnet spherical motor (PMSM) trajectory tracking control method to ensure the robustness of the system and the fastness of tracking control. However, this conservative control will bring greater control, and even lead to actuator saturation. In order to reduce the conservativeness of control, this paper designs a fuzzy sliding mode controller with nonlinear disturbance observer to solve the trajectory tracking problem of PMSM. The nonlinear observer is used to estimate the uncertainty, friction, external disturbance and load disturbance, and compensate it at the control input so as to achieve the suppression of interference. The sliding mode controller is used to cancel the interference observation error of the disturbance observer and unobservable part disturbance. In order to reduce the undesirable chattering phenomenon, the fuzzy logic is used to approximate this part. And the sliding mode switching gain is replaced by the fuzzy output gain. In addition, the stability of the controller is proved by the Lyapunov equation. The simulation results show that the proposed algorithm can realize PMSM trajectory tracking control in the presence of model uncertainty and various disturbances, and has good dynamic and static performance and less conservativeness.